FOOD AND

8Aa
You would not see adverts like the ones on this page today!
There are now much stricter rules on the claims that a food
advert can make. A claim is a statement that is supposed
to be true. Adverts often contain claims to convince you to
buy a product. Many countries now have laws that say that
all health claims must be supported by scientific evidence.
We also know much more about the effects of food on the
Riche's theory becomes
body today. Scientists think that foods that are high in fat - every child can now h
oaturally wavy hair t hat
and sugar can cause people to put on too much weight. For remain wavy throughout life
• GLUG' Is the vitamin hair
this reason, these t ypes of foods cannot be advertised on food that promotes wavy hair.
• GLUG ' is not a setting
children's TV. Iotlon ; and It Is absolutely
safe to use.

II Why do we need t o eat food?

II Look at advert A.

a I What claim is being made? Obroinable from High Cfoss Chemises Price
or Stores. In case of diffrculty 1 2 /6
write direct ( including 6d. for posting & packing) (6 month suppl y)
bl Suggest why a company would not be able to make RICHE or Hay HIii Ltd., 14, Hay Hill, Berkeley Squore, London, W .1
th is claim today.
A I This advert is from 1952.

II Look at t he advert for

doughnuts (B).

a I Explain why t hese

doughnuts are supposed
to be good for you.

bl Suggest w hat is wrong

\111//;,\\ w _·
with eating too many

■
doughnuts.

a l In w hat organ system is

1TAM~,\~
food broken down and
taken into t he blood?
\\\ DONUTS
bl Name two parts of t his
organ system.

cl Describe t he f unctions of
t hese parts.

II Suggest one thing people

should do in order to eat
healthily.
UK NC, iLS, CEE

_SA
WHAT DOES OUR FOOD CONTAIN?

In science, the word diet means what you eat. Your diet provides
raw materials for your body, which are needed for energy (to move, II What do scientists mean
by diet?
keep warm, make new materials), growth and repair, and health.
a I What is a nutrient?
Food substances that provide raw materials are called nutrients. II
These include carbohydrates, fats, proteins, vitamins and minerals. bl What does your body
use nutrients for?
The main carbohydrates in food are insoluble starch and soluble
sugars. There are many different sugars, including sucrose (table
sugar) and glucose.
There are many different sorts of fats. Some are solid and some are
liquid at room temperature. We call liquid fats oils. Fats and oils are
sometimes called lipids.
We also need to eat fibre. This is made of plant cell walls and is
not used by the body, but it keeps us healthy by helping food
move through the intestines and stopping them getting blocked
(constipation). Wholegrain cereals and breads contain a lot of fibre.
Water is also very important since about 65 per cent of you is water!
Water:
■ acts as a lubricant
• dissolves substances so that they can be carried around the body
■ fills up cells so that they hold their shape
■ cools you down, when you sweat.

■ How are water and fibre helpful for preventing constipation?

II Full Bran is a new cereal that contains a lot of fibre. Write a health
claim for use in a Full Bran advert. -,., n:,%11
counr as o
~ '"""'1 2 ;;-;:-:---'lli,;;;:;:.--
DA) and addin • .Jg f•t •nd I ss
ne of Your S-a-o 9 a handful of f "'9 of

II Explain why you should drink plenty of water in hot weather.

Typical values

Energy
ay.
lOOg
contains
ru11 "'Ill

459 serving
1S70kJ contains
l7Skcaf 7lOkJ

Food labelling 10.Jg

73.Bg
15.0g
170kcaJ
4,69
33.29
2.0g 6.89
Nutrition information labels show the amounts of different nutrients 0.3g 0.99
in a food. You can compare the nutrients in different foods using the 8.2g 0.19
ulva/ent 0.29 3.79
'per 100 gram (g) of food'values. You cannot compare foods using 'per has be 0.6g 0. 1g
serving of food; since servings of different foods are different sizes. del en determined by AOAc -"ft••· . 0.Jg
Nutrition labels also show the amount of fibre and
the amount of energy stored in the food. II List the names of the nutrients on label B.

Food labels have a list of ingredients and highlight

substances that people may be allergic to (e.g. nuts, II Suggest why a breakfast cereal box states:
'May contain traces of nuts'.
eggs). Labels also show warnings about substances
that can cause problems. For example, in Europe, II The food referred to in label B contains two
carbohydrates: starch and sugars. How much of
if a drink contains a lot of caffeine, the label will each is there in one serving?
state: 'Not suitable for children, pregnant women
and persons sensitive to caffeine:

Testing foods In 2013, tests in Europe discovered that many

products that claimed to be 100 per cent
In many countries, government scientists test food
beef actually contained horse meat.
to make sure that labels are correct. Photos C, D and
E shows tests for starch, protein and fats.

II Gita tested butter and bread with iodine

solution. Which nutrient was she testing for?

m 100 g of a milk powder contains 27 g of fat,

38 g of carbohydrate and 26 g of protein.
a I Describe how you would test for the
nutrients in milk powder and what results
you would expect.
bl Why do the totals of the nutrients not add
up to 100 g?

I can ...
■ recall the nutrients we need in our diets
■ interpret nutrition information labels
■ recall the tests used to detect some nutrients.
 USES OF
UK NC, iLS, CEE

_8Ab
WHY DO WE NEED THE DIFFERENT NUTRIENTS?

Different nutrients are used for different things in

your body. II List all the different types of nutrient in food.

For energy

~
When you eat food, you gain mass. When doing
everyday activities, the fuel in your food is used
up and so you lose mass. To make sure your mass
does not change, the amount of fuel you use
should be balanced by the amount you eat.
Your body's main source of energy is
carbohydrates. There is a lot of starch in foods
like bread and potatoes, and sugars are found
in sweet foods. Another source of energy comes
p @L _
~;;a,, \ , v;
from fats. There are a lot of fats in dairy products
and fried foods. ~==* ==r
Fats are stored in your body so that there is
always a source of energy. A lot of this stored fat You gain mass You lose mass doing
comes from the fats that you eat. However, if the when you eat. everyday things.
carbohydrates you eat are not all used up, they can
be turned into fat. Some fat is stored under your A I The amount of energy stored in your food should
balance the amount of energy that you need.
skin to insulate your body and help you stay warm.

II Gareth's mass has increased. Suggest why.

II Why do you need starch in your diet?

II What does your body use fat for?

Energy transfers
Different foods contain different amounts of
energy, which is measured in kilojoules (kJ).
Respiration in your cells releases the energy.
As your eel Is respire, the energy is transferred
(moved) from the nutrients, making it available
for you to grow, move, think and keep warm.
The amount of energy your body needs to
transfer depends on your age, whether you are
male or female and how active you are.
 II
How daily energy requirements change with age

14000~ - - - - - - - - - - - -
■ Male
Activity Energy required per hour (kJ/h) 13000
■ Female
~ 12000
Sleeping 180 --,
: 11 000
Watching TV 250
.gJ 10000
Walking slowly 470 [i
Cl. 9000
Cycling slowly 660 "'O
8000
.~
::J
Cycling quickly 1090 CT 7000
~
Running fast 1700 >. 6000
e>
QJ
C
QJ
I 4000
II a Look at label Bon page 6. How much energy is in 100 g
of the food?
QJ
0)
~
QJ
3000
bl How much of this food would provide the energy ~ 2000
needed by someone of your age and sex for one day? 1000
c I How much of the food would provide the energy for 0
2 hours of slow walking?

I
a Between which ages do people need most energy?
II bl Suggest a reason for this.
Age (years)

II al Ravi is a fitness trainer. His wife is the same age and works
at a call centre. Who will need more energy per day?
bl Explain why this is.

II Jasmine eats more carbohydrates than she needs for energy.

Explain why her mass will change.

Growth and repair

Proteins are very important for making new cells to help us to
grow and repair our bodies. Proteins are found in foods like
meat, fish, eggs, cheese, beans and milk.

For health
All nutrients are important for health, and these include
tiny quantities of vitamins and mineral salts (usually
just called minerals). For example, vitamin A is needed
for healthy skin and eyes, and vitamin C helps cells
in tissues to stick together properly. Vitamin D and
calcium are needed to make bones, and iron is used to
make red blood cells.

II Give three important reasons for eating food.

I
II a State two good sources of each type of
nutrient found in food.
I can ...
bl Why do our bodies need each type of
nutrient? Present your answer as a table. ■ recall good sources of different nutrients

m Suggest one effect of a lack of iron on your

body. Explain your reasoning.
■

■
describe how factors change the amount of energy
we need
describe what each nutrient does in the body.
 UK NC, iLS, CEE

_8Ac
WHY IS A BALANCED DIET IMPORTANT?

It is recommended that you eat five Bread, rice, potatoes and

No single food contains all the substances portions of fruits and vegetables pasta contain lots
per day. They are rich in fibre of starch.
that you need, so you must eat many d ifferent and many vitamins and
foods. If you eat the right amounts of a wide minerals.
variety of foods you have a balanced diet.
People who have a problem caused by too
much or too little of a nutrient in their diets are
said to suffer from malnutrition.

II What is a balanced diet?

II Why is someone who is very overweight

suffering from malnutrition?

Meat, fish, beans, Milk and dairy

Deficiency eggs and nuts contain
lots of protein. Beef
Foods and drinks high foods (things made
from milk) are good
diseases and eggs are good
sources of iron.
in fat and/or sugar. You
should only have these
as an occasional treat.
sources of fat and
calcium.
People who lack a nutrient for a long time Public Health England in association with l he Welsh Government, the Scottish Government and the Food
Standards Agency in Northern Ireland
can suffer from a deficiency disease.
A lack of protein can cause kwashiorkor A I The Eatwell Guide helps people to eat a balanced diet. It
shows how much you should eat from different food groups.
(pronounced 'kwash-ee-or-ker'). One symptom
is a large belly, caused by fluid collecting around
the intestines and muscles that become too weak to
hold the stomach and intestines in place.
A lack of vitamin A causes night blindness (not
being able to see well in low light). Scurvy is caused
by a lack of vitamin C, and causes painful joints and
bleeding gums.
A lack of calcium and vitamin D can cause rickets,
in which weak bones do not form properly.
Tiredness and shortness of breath are symptoms of
anaemia, caused by a lack of iron.

a I What disea ses are shown

II in photos Band C.
Explain your reasoning.
bl Suggest a change that
someone could make
to their lifestyle to cure
scurvy.

a
Starvation
The worst form of malnutrition is starvation, in which people
lack nearly all the nutrients they need. People who are
starving get thinner and thinner.

Obesity
People whose food contains more energy than they need
may become overweight. This can cause heart disease,
when fat clogs the arteries and stops enough blood reaching
the heart muscle tissue. If very little blood reaches the heart
muscle, it can start to die (a heart attack), which causes a
painful squeezing feeling in the chest.
People who are overweight are more likely to have high
blood pressure, which can damage the heart or kidneys or
cause blood vessels to burst.
People who are very overweight are said to be obese. Obesity
is increasing in many countries, so some scientists want to
stop adverts for fatty or sugary foods.

II How will a balanced diet stop people becoming

overweight?

a I What condition is the man in photo E suffering from?

II bl Suggest why he has developed this condition.
c I What health problems is he more likely to develop?

Help with your diet

Many nutrition information labels give people an idea about
how much of each nutrient can be eaten in a day. These
Reference Intakes (or Rls) are usually shown for adults.
a I How much wholemeal bread would
Note: 1 mg (milligram) = 0.001 g;
1 µg (microgram) = 0.000001 g.
II an adult need to eat for it to provide
all their energy needs for a day? Give
100 g of 100 g of 100 g of
Reference wholemeal oranges butter
your answer to the nearest 100 g.
Intake (RI) bread contains contains contains bl Suggest why only eating wholemeal
energy 8400k.J 920 kJ 150 kJ 3000 kJ bread would be a bad idea.
carbohydrate 260g 38.4 g 8.5 g 0g
c I In what way would putting butter on
protein 50g 10.3 g 0.8g 0.5 g
the bread be good?
fat 70g 2.5 g 0g 81g
1ibre 24g 6.5 g 2.1 g 0g
vitamin A 800 µg 0 µg 5 µg 887 µg
vitamin C 60mg 0mg 50mg 0mg I can ...
calcium 800mg 28mg 41 mg 15 mg
iron 14 mg 3mg 0.3mg 0.2 mg ■ describe the benefits of a balanced diet
■ explain the causes and effects of some
different types of malnutrition.

L11
-------------------
Give one advantage of canned foods.

Give two reasons why food technologists

invent new foods today.

Suggest two advantages of killing microorganisms in

foods using electricity rather than heat.

A food packet claims that the food contains starch. Explain

how a food technologist would test this claim.
Suggest t wo ways to make a snack
bar with less sugar.

Explain one new food product that

you would like to see for sale.

People have asked a pizza company to

use healt hier pizza bases. The nut rit ion
Ingredients
information for t he existing pizza base Bleached white flour, water, glucose, sucrose,
is shown. salt, hydrogenated vegetable oil (to add
stretchiness), xanthan gum (to add stretchiness)
State some ways in w hich t he pizza base
Nutrition Information
could be made healt hier.
Typical values per 100g per serving
2 Choose one way and explain two ideas (¼ base)

for changing t he pizza base in this way. Energy 1059 kJ 585 kJ

Protein 9g 5g
3 Choose one idea and design a delivery
Carbohydrate 62g 34g
box to advert ise your new pizza base.
of which sugars 14g 8g
Fat 5g 2.5g
Fibre 0.2g 0.1 g
Allergy advice Product contains gluten
 UK NC, iLS

_SA
WHAT DO THE PARTS OF THE DIGESTIVE SYSTEM DO?

Proteins, fats and most carbohydrates are too big for your body to use
a I What does the
and need to be broken down into smaller pieces. Digestion turns large II digestive system do?
insoluble molecules into smaller soluble ones. Digestion occurs as your
b I Why do we need to
food passes through your gut (a tube made up of different organs). The
digest food?
gut and some other organs that help digestion (such as the salivary
glands, liver and pancreas) form the digestive system.

1. Putting food in your mouth is 2. When you swallow, food enters

ingestion. Your teeth grind the oesophagus (or gullet). Muscles
food into small pieces and mix in the oesophagus contract to make the
it with saliva, which is tube above the food narrower, and this
produced by your salivary pushes food towards the stomach.
glands. Saliva is an example of Food is moved through the whole
a digestive juice - it helps gut in the same way.
digest food. It also makes food
easier to swallow.

3. In the stomach ,
food is churned up
with acid (pH 1- 2)
salivary glands and more digestive
juices are added.
pancreas
4. In the small
intestine, more 5. Food that we cannot
digestive juices are digest (e.g. fibre) goes
added (including from into the large intestine,
the pancreas). The liver where water is removed.
adds a substance to This forms a more solid
help digest fats. Small material called faeces
molecules of digested (pronounced 'fee-sees').
food are then
absorbed (taken
into the body) here. 6. The rectum stores faeces, which are
then pushed out of the anus in a process
called defaecation or egestion. It takes
anus about 24-48 hours for food to go through

■
the gut. (Note that defaecation is getting rid of
undigested food. Excretion is getting rid of
wastes produced by your cells.)

II Draw a flow chart to show what happens in

each organ of the gut.

II What are ingestion and egestion?

■ Describe how food is pushed through the gut.

ll1J
Gut bacteria
Bacteria are microorganisms (organisms you need
a microscope to see). Although they are tiny, your
intestines contain about 1 kilogram (kg) of them!
Some of these bacteria are useful, but other types
are harmful.
The bacteria in your gut feed on your food and
can digest some foods that your body cannot. The
bacteria grow and reproduce using some of these
digested molecules, but the rest of the molecules
can be absorbed into your body.

Enzymes
Enzymes are substances that speed up the breaking down of large molecules
into smaller ones. Substances that speed up reactions (without being changed
themselves) are called catalysts. Enzymes are biological catalysts.
Most of the enzymes needed for digestion are produced by your body and
are found in the various digestive juices that are added to food as it travels
through the gut.
A model that helps us think about how enzymes work compares them to
D I the scissors model of
scissors. The enzymes help to cut through the connections that hold the
enzyme action
molecule together.

II Give one benefit and one disadvantage of

having bacteria in your gut.
I can ...
■ recall the parts of the digestive system and their
a I How do digestive juices help with digestion?
II bl Use the scissors model to explain how
functions
■ explain why enzymes and bacteria are useful for
enzymes work.
digestion.

L1s
-----------------------
iLS

8AeSURFACE AREA
HOW ARE SURFACE AREAS CALCULATED?

The area of a rectangle is worked out using

this formula:

area of a rectangle = length x w idth

Area is measured in square units, like metres

squared (m2), centimetres squared (cm 2),
millimetres squared (mm 2). So, if the length
and width are in metres (m), the area is in m2.

A tennis court is a rectangle 23.78 m long

and 10.97 m wide:

area = 23.78 x 10.97

= 260.87 m 2

II What is the area of a soccer pitch that is

100 m long and 45 m wide? Show your
working.

The total area of all the surfaces on a three-dimensional shape is called

the surface area. It is important because it can affect t he speed at
which things happen.

Radiators and air conditioning evaporators have folds or fins o n them

to increase their surface areas. This means that more energy can be
transferred from them in a certain length oftime.

Calculating surface areas

A cube has six faces. To find the surface area of a cube you find the area
of each face and add them all together. Some cells are roughly cuboid,
so we can estimate the total su rface area by finding the total of the
B I Air conditioning areas of a cell's six rectangular faces.
evaporators have large
surface areas.
top area = 12x10
= 120µm2
front area = 12x10
■
= 120µm2

end area= 10x10 2 - --+-- 0 , --- }Oµm

= 100µm _

~ ~- - - -1
10µm 1 12µm

a
In diagram C, the top face of the cell is the same size as
the bottom face, so:
Area of top and bottom = 120 + 120 = 240 µm 2
2
II Estimate the surface area of
an approximately cuboid cell,
Area of front and back= 120 + 120 = 240 µm
with length 10 µm, width 15 µm
Area of both ends= 100 + 100 = 200 µm 2 and height 20 µm. Show your
working.
Surface area of the cuboid= 240 + 240 + 200 = 680 µm 2
If food is given a greater surface 6cm 3cm 3cm
3 cm 41 ~ 41 ►
area, there is more room for 6~ 3cm
enzymes to get to work and break
down the food. This is why, for
example, teeth are important for 3cm I . . . , . . _ _ ~ ~,
grinding up food. 6cm

Surface area is also important for

3cm I ..___.._____.
the small intestine; the larger its
surface area the faster it can absorb
surface area of large cube: if the large cube is split into
digested food. eight smaller cubes:
6 x (6 x 6) = 216 cm2 surface area of one smaller cube = 6 x (3 x 3)
= 54 cm2
II A cuboid measures 8 cm long,
4 cm wide and 6 cm tall. there are eight smaller cubes,
so total surface area = 54 x 8
I
a Calculate its surface area. = 432 cm 2
bl The cuboid is cut in half along
its longest edge. Calculate its D I If the big cube is broken down into many smaller cubes, there is
new surface area. a big increase in surface area.

Surface area : volume ratio

II Explain why a sugar cube
dissolves more slowly in a cup of
The surface area: volume ratio is the surface area divided by
coffee than the same amount of
loose sugar granules.
the volume, or surface area
volume
The bigger the surface area: volume ratio, the more surface area
II Explain why the same amount of
food is digested faster when it is something has per unit volume. Cells need large surface area :
in small pieces compared with
volume ratios to be able to take enough of the substances they
large pieces.
need from their surroundings.

■
Look at diagram D. Calculate the
surface area: volume ratio of:
I
a the large cube
bl one of the small cubes. I can ...
Show your working. ■ calculate areas of rectangles and cuboids
■ explain the importance of surface area in
science, including surface area : volume
ratios.
L11
-----------------
_SA
HOW DOES DIGESTED FOOD GET INTO THE BLOOD?

Enzymes break up large molecules into smaller, soluble ones. enzyme

The small molecules can then be absorbed by the small intestine.

a I Where is digested food absorbed?

II bl Explain which molecules in diaigram A can be absorbed.

Models help us to think about how complicated things happen.

...
Diagram Bis a model of the small intestine. Visking tubing is a thin o o• • •
material containing tiny holes that only small molecules can pass
through. In diagram B the inside of the tubing represents the inside of smalle~ lucose~
the small intestine. The water around the tubing represents the blood. molecules

A I Starch is digested into

Visking tubing smaller sugars, such as
glucose, by enzymes.

mixture of water,
- - - - + -- enzymes and starch
_.,___ water
BI model
small tightly tied II What would you expect to find in the water at
the end of the experiment shown in diagram
intestine B that was not there at the start? Explain your
reasoning.

a I Why do your cells need to respire?

Once absorbed, digested nutrients are dissolved
in the blood plasma (the liquid part). Blood carries
II bl Which parts of the blood carry the
the nutrients around the body for cells to use. For substances needed for respiration?
example, all your cells need glucose in order to
release energy (using respiration).
All particles naturally spread out. This is called Glucose Water
molecules. molecules
diffusion. If there are more particles of a substance move in move in
in one area than another, eventually the particles random random .
directions. directions. even spreading
become evenly spaced due to diffusion. After a meal, "' A of molecules
there are many more digested nutrient molecules b•\. 1
✓j • wall of small • •• • 1I • •• •
• '- • • _ _ -
inside the small intestine than in the blood. This • • i------- • intestine • • •• •
• • • - 1• • • • • I •
causes an overall movement of these molecules into
0
•♦ • 0 - •
• •• -===r:.i. •0 • •
•e ••
•• I• • • • • I.:, •
the blood, by diffusion. •• •- • diffusion • • • • • •
10 . , . • •• , • ••
• • - Q
Particles move randomly in all directions. So some I • • • • I • a• •
inside small in blood
molecules of glucose will move from the blood intestine
into the small intestine, but many more go the
other way. There is an overall movement of glucose C I diffusion in the small intestine
molecules in one direction.

a
II What is diffusion? Small intestine
Why do some glucose molecules move out of adaptations
II the blood and others move into it? The greater the surface area, the more room there
is for molecules to pass between the inside of the
II Explain how diffusion allows the small intestine
to absorb soluble molecules but not insoluble small intestine and the blood. So, a greater surface
ones. area allows more diffusion of molecules. This allows
more glucose to be absorbed more quickly.
To increase its surface area, the wall of the small
intestine is folded. It also contains lots of little
The surface area of the small intestine finger-shaped villi (one is called a villus).
is about the area of a tennis court
{about 260 m2 ). To further increase surface area, each villus cell has a
folded top (that forms microvilli, one is a microvillus).

The wall of the villus is only one

cell thick so that substances
do not have to diffuse very far.
vein This increases the speed of
~.....,/~"J•----- absorption.

O O O~ O~ C ~~
{($ ~ 00 0 ~
0 0 \ <~
capillaries 0 nucleus
{o
"""'
~ mitochondria

small intestine

D I The small intestine is adapted to its function.

Alcohol
■
How is the small intestine adapted to absorbing
digested nutrients quickly?
When alcohol is drunk, fewer digestive enzymes are
a I Give one short-term effect of drinking alcohol
II on the digestive system.
released into the small intestine. Drinking alcohol
can damage the villi and cause them to become
bl Explain why this may cause fewer nutrients to shorter.
get into the blood.
cl Explain why someone who drinks alcohol may
suffer from malnutrition.
lean-
II You can think of the human small intestine as a tube
which is about 6.5 m long and has a diameter of ■ explain how diffusion enables absorption by the
2.5 cm. A tube of these dimensions has a surface small intestine
area of about 0.51 m 2. Why is this different from ■ explain how the small intestine is adapted to its
the area given in the fact box? function.

___________________ ....
L19
 Most food companies put nutrition information
labels on food packaging. Many companies also
add traffic lights. Red means high, orange means
medium and green means that a foo d is low in a
certain nutrient. The more green the better. The
percentage of t he Reference Intake in a serving
may also be shown.
Co mpanies m ust show ingredients o n packaging
and m ost foods must be dat ed. A 'best before'
date t ells you how long a food's t aste w ill be at its
best. A food is usually safe to eat after this date
but does not tast e as good. Food s w ith a 'use
by' date may cause harm after this dat e, often
because harmful bacteria grow in them.

■ a I Suggest why food producers use

BEST BEFORE (DD/IIMIYY)

II words like 'finest' on their foods.

25 .06 .12 bl Suggest why food producers

Jt.aAi•ilil(fl/111-l-) advertise some foods as ' light'.

a I List the different types of nutrients

II in photo A.
In some countries there are strict rules on some words found bl What does each nutrient do?
on food packaging. For example, in the EU foods labelled c I Suggest w hy only certain nutrients
'organic' must be produced w ithout the use of artificial appear on food traffic lights.
fertilisers and pesticides. A low fat food must contain less
than 3 g of fats per 100 g of food. A reduced fat, light or 'lite' II Describe how bacteria can be bot h
useful and harmful in the digestive
food m ust contain 30 per cent less fat or energy than another system.
food of the same type.
However, many other w ords have no rules, including II Draw a flow chart to show how cells
get a fuel for respiration after you have
'traditio nal st yle; 'finest ' and 'handmade'. eaten starch.